One known secret data storage device has the secret function which stores the data unwilling to be known to others except for particular users and the important data as secret data and enables the stored secret data to be accessed and read, only when the previously entered user's unique registration password coincides with the user-inputted collation password.
To prevent others from seeing the secret data easily, password data difficult for others to understand is set. In setting the password data, a combination of numbers into a four-digit number or a combination of characters or symbols has been used.
Setting password data in the form of such a combination makes it very difficult for the user to memorize and input the data.
The present invention has been considered to solve the problem with the prior art.
Accordingly, the object of the present invention is to provide a secret data storage device capable of accessing the secret data using a password easy for particular users to memorize but difficult for others to understand, a method of reading the secret data, and a storing medium for control programs.